Re: [PATCH 1/4] fsmonitor: Watch, and ask about, the top of the repo, not the CWD

From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Oct 27, 2017, 15:11 UTC
Message-ID: <alpine.DEB.2.21.1.1710271709570.6482@virtualbox>
In-Reply-To: <alpine.DEB.2.10.1710251700300.9817@alexmv-linux>

Hi Alex,

On Wed, 25 Oct 2017, Alex Vandiver wrote:

Show 9 quoted lines

> On Fri, 20 Oct 2017, Johannes Schindelin wrote:
> > This is super expensive, as it means a full-blown new process instead of
> > just a simple environment variable expansion.
> > 
> > The idea behind using `PWD` instead was that Git will already have done
> > all of the work of figuring out the top-level directory and switched to
> > there before calling the fsmonitor hook.
> 
> I'm not seeing that PWD has been at all altered.

No, PWD is not altered.

But a simple environment variable expansion (fast) was replaced by spawning to `git rev-parse --show-top-level` (slow, ~60ms on Windows).

*That* is expensive.

Ciao, Johannes